Silsilat al-Ahadith al-Sahihah

It is narrated from Sayyiduna Abdullah bin Amr (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) said: “Allah will have mercy on those who are merciful, so be merciful to those on the earth so that the One in the heavens will have mercy on you. (In reality) mercy (i.e., maintaining ties of kinship) is a branch of the Most Merciful. Whoever joins it, Allah will join him, and whoever cuts it off, Allah will cut him off.”